User`s guide
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NAT
NAT (Network Address Translation) is the translation of an Internet Protocol address () used in 
one network to a different IP address known in another network through a NAT table that does 
the global-to-local and local-to-global IP address mapping. This increases security since each 
outgoing or incoming request must go through a translation process that also authenticates the 
request or matches it to a previous request. NAT can be statically defined or it can be set up to 
dynamically translate from and to a pool of IP addresses. NAT also conserves on the number of 
global IP addresses needed and it uses a single IP address in its communication with the world. 
PEAP
See Protected Extensible Authentication Protocol.
port forwarding
A serial port configuration that sends data directly to a specific port instead of the path 
determined by the router based on traffic.
Power-On Self Test (POST)
When power is turned on, POST (Power-On Self-Test) is the diagnostic testing sequence that a 
computer's basic input/output system (or “starting program”) runs to determine if the computer 
keyboard, random access memory, disk drives, and other hardware are working correctly. If the 
necessary hardware is detected and found to be operating properly, the computer begins to boot. 
If the hardware is not detected or is found not to be operating properly, the BIOS issues an error 
message which may be text on the display screen and/or a series of coded beeps, depending on 
the nature of the problem.
Protected Extensible Authentication Protocol (PEAP)
A protocol proposed for securely transporting authentication data, including passwords, over 
802.11 wireless networks. PEAP makes it possible to authenticate wireless LAN clients without 
requiring them to have certificates, simplifying the architecture of secure wireless LANs.
RCI
See Remote Command Interface.
RealPort
Patented Digi software for COM port redirection. RealPort makes it possible to establish a 
connection between the host and networked serial devices by creating a local COM or TTY port 
on the host. 
The COM/TTY port appears and behaves as a local port to the PC or 
server. This process of COM port redirection allows existing software applications like DNP3 
and Modbus to work without modification. Unlike other COM port redirectors, RealPort offers 
full hardware and software flow control, as well as tunable latency and throughput. These 
features ensure optimum performance, since data transfer is adjusted according to specific 
application requirements. 










